We love Jetblue. The regular seats have more leg room than other airlines, they have very yummy snacks (more variety than others) and every seat has it's own TV. They do credit if your price goes down (you have to call them) & you have a year to use the credit. That is a year fron the date you got the credit, not a year from when you booked like Southwest.
However they do charge a fee if you need to change the flight, unlike Southwest which lets you change for free. I think it is $100 per person to change, so be sure before you book.